1. Field of the Invention
This invention relates to a base metal conductor multilayered substrate capable of being integral with thick film components such as thick film resistors, and to a manufacturing method for the substrate.
2. Description of the Prior Art
Conventionally, a ceramic base metal conductor multilayered substrate in alumina-tungsten series, or alumina-molybdenum series, has been well-known, and has been widely used as packages for IC or LSI. On the other hand, a ceramic multilayered structure in this series has also been used as the multilayered substrate for packaging multipin semiconductors. In this case, the multilayered substrate mainly comprises the uppermost plated layer and parts subjected to wire bonding or soldering.
Recently, in the growing demand for miniaturization of apparatus, small-sized modularization and automatic adjustment of circuits have been required so that the substrate having a multilayer wiring structure and capable of being integral with thick film parts, such as thick film resistors, has been highly in demand. Such substrate, however, becomes oxidized in atmospheric air at a high temperature because its conductor is formed of tungsten or molybdenum and restricted in the chemical property. Therefore, it has been difficult to form thick film glaze resistors required to be sintered in air at a high temperature.